1. Field of the Invention
The present invention relates to a communicating apparatus that includes a security function, a communicating method, and a computer program product.
2. Description of the Related Art
In many instances, along with development of a wireless technology, communication, which was typically carried out by wired connections, is now changed to wireless connections. For example, in a local area network (LAN), Ethernet (registered trademark) connections typified by Institute of Electrical and Electronics Engineers (IEEE) 802.3 were predominantly used. However, in recent years, many data communicating apparatuses are using wireless LAN connections typified by IEEE 802.11 system. The usage of wireless communication is increased not only in the LAN but also in a personal area network (PAN).
Based on physical properties of wireless communication, any individual can receive a packet transmitted by the wireless connections. Thus, a security function is necessary for preventing interception of the packet and protecting privacy. Generally, an authenticated method that uses a common key is used as a security function implementing method. However, prior exchange of the key between communicating parties is necessary in a common key system. Thus, the key exchange, which is not required in wired communication, is severely hampering convenience of wireless communication.
Various methods have been developed for enhancing convenience of the key exchange. For example, a technology is proposed in Japanese Patent Application Laid-open No. 2005-318079 in which terminals are interconnected by a wire cable and the key exchange is carried out in wireless communication when an electric potential of the cable is active.
In the technology mentioned earlier, irrespective of carrying out wireless communication, drawbacks such as inconvenience due to requirement of the wired connections, and a cost increase resulting from arrangement of a specific wire interface are not overcome.